Desperate, tempted to sell!

As you put more and more mods on your car for max power you will see a decline in the drivability of your car and a steady idle is one of the major frustrations of all of them.

Go over to one of the tuner sites and you will see that most of the talk is about trying to get back some drivability and a good idle is the focus of most of those threads.

Even with all mechanical adjustments correct and having access to fine tune the values in the pcm it can be a time consuming task to achieve a good steady idle.

After I put on heads & cam my drivability was really bad and at that time I was using the stock maf which you know has the correct transfer curve.

I did not make very much headway with slaying the drivability gremlins until I made some adjustments to the pcm's values to compensate for the all of the hot rod parts.

I do feel your frustration but it seems that each combo is different cause some have more probs than others and the fix is different for some than others

Later
Grady

I agree with mo_dingo. Drop the idle and give the computer some time to learn. Try to drive it around the block a few times.

my check engine light does not come on, will i still have codes to pull?

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I would check for codes if you haven't already done it. You could have some trouble codes stored without the CEL coming on. Besides, it only takes 5 minutes to do and then you've eliminated that possible cause of your idle problems.

One more thing, as I mentioned in my earlier post, how old are you're IAT/ECT sensor's (O2 sensor's too for that matter)? They have been known to cause problems when they get old. They're output goes all wonky, but not enough to hit the preprogammed limit that would cause the PCM to notice and trip a CEL. The car starts to run less then ideal and the PCM tries to compensate by adjusting a/f ratio (injector pulse) among other things. Now the car has the wrong a/f ratio for the conditions which will cause a number of other problems as I'm sure you are aware. One of those being, your idle is going to be off a bit. The PCM tries to adjust the idle speed with the IAB valve, but its making those adjustments based on the assumption that the input from the other sensor's are accurate, when in fact they're not.

Because the information from some of the sensor's is inaccurate (IAT/ECT in this case), the PCM adjusts IAB valve incorrectly and doesn't see the idle speed it was expecting, it again adjusts the IAB valve to try and get the idle where it's supposed to be, again using the data from the inaccurate sensor's.......you can see where this is going right? Wandering/fluctuating idle. Throw some performance parts into the mix with inaccurate sensor's, and well, good luck getting a steady idle.

Long story short, replace your IAT/ECT sensor's if they are old!! (well under $100 for the pair) (O2 sensor's too!! They're only good for about 80,000 miles under optimum running conditions)